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  <h2>Navigation Bars</h2>
  <p>The <strong>w3-bar</strong> class is a container for displaying HTML elements horizontally.</p>
  <p>The <strong>w3-bar-item</strong> class defines the container elements.</p>
  <p>It it a perfect tool for creating navigation bars:</p>
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  <p>The <strong>w3-mobile</strong> class defines responsive elements.</p>
  <p>Resize the browser window to see the effect:</p>
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